For what I said before, I think it is useful to remember that in the Middle Ages the sun and the moon were considered planets. In the Voynich we don't seem to see Mercury, Mars, Venus, Jupiter, and Saturn, but we do see the Sun and Moon, the other medieval planets, frequently. That is why the planetary aspects or geometric relationships that we see in the You are not allowed to view links.
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Login to view. are relevant. They are the relationships between the sun and the moon and we see them duplicated, two suns and two moons, in order to form the geometric figures of the aspects: trine, quadrature, etc.
In the Rosettes folio we see the astronomical clock with a trine aspect, that is, the sun forms a triangle with the moon (two moons, one on each half of the sphere). It should be noted that this aspect, the trine, was one of those considered to be the most positive, which marks the Rosettes with a beneficial aura.
I think this is of secondary relevance to the Voynich, but it is a sign of the importance of medieval astrology in understanding the book.